Enhancing Li-Ion Battery Anodes: Synthesis, Characterization, and Electrochemical Performance of Crystalline C Nanorods with Controlled Morphology and Phase Transition.

Recently, C has emerged as a promising anode material for Li-ion batteries, attracting significant interest due to its excellent lithium storage capacity. The electrochemical performance of C as an anode is largely dependent on its internal crystal structure, which is significantly influenced by the synthesis method and corresponding conditions. However, there have been few reports on how the synthesis process affects the crystal structure and Li storage capacity of C.

Low-Index Facet Polyhedron-Shaped Binary Cerium Titanium Oxide for High-Voltage Aqueous Zinc-Vanadium Redox Flow Batteries.

Aqueous zinc-vanadium hybrid redox flow battery systems are an efficient strategy to address the problems of low voltage and high cost of conventional all-vanadium redox flow batteries. However, the low electrochemical activity of carbon-based electrodes toward a vanadium redox reaction limits the performance of redox flow batteries. In this study, polyhedral binary cerium titanium oxide (CeTiO, CTO) is synthesized using molten salt synthesis.

Enhanced High-Rate Capability and Long Cycle Stability of FeS@NCG Nanofibers for Sodium-Ion Battery Anodes.

The development of advanced hierarchical anode materials has recently become essential to achieving high-performance sodium-ion batteries. Herein, we developed a facile and cost-effective scheme for synthesizing graphene-wrapped, nitrogen-rich carbon-coated iron sulfide nanofibers (FeS@NCG) as an anode for SIBs. The designed FeS@NCG can provide a significant reversible capacity of 748.

Flat-surface-assisted and self-regulated oxidation resistance of Cu(111).

Oxidation can deteriorate the properties of copper that are critical for its use, particularly in the semiconductor industry and electro-optics applications. This has prompted numerous studies exploring copper oxidation and possible passivation strategies. In situ observations have, for example, shown that oxidation involves stepped surfaces: CuO growth occurs on flat surfaces as a result of Cu adatoms detaching from steps and diffusing across terraces.

Abnormally High-Lithium Storage in Pure Crystalline C Nanoparticles.

Li intercalates into a pure face-centered-cubic (fcc) C structure instead of being adsorbed on a single C molecule. This hinders the excess storage of Li ions in Li-ion batteries, thereby limiting their applications. However, the associated electrochemical processes and mechanisms have not been investigated owing to the low electrochemical reactivity and poor crystallinity of the C powder.

Color of Copper/Copper Oxide.

Stochastic inhomogeneous oxidation is an inherent characteristic of copper (Cu), often hindering color tuning and bandgap engineering of oxides. Coherent control of the interface between metal and metal oxide remains unresolved. Coherent propagation of an oxidation front in single-crystal Cu thin film is demonstrated to achieve a full-color spectrum for Cu by precisely controlling its oxide-layer thickness.

Lithium Attachment to C60 and Nitrogen- and Boron-Doped C60: A Mechanistic Study.

Fullerene-based materials including C and doped C have previously been proposed as anodes for lithium ion batteries. It was also shown earlier that - and -doping of small molecules can substantially increase voltages and specific capacities. Here, we study ab initio the attachment of multiple lithium atoms to C, nitrogen-doped C (-type), and boron doped C (-type).

A study of the density of states of ZnCoO:H from resistivity measurements.

Understanding the electronic band structure and density of states (DOS) of a material and their relationship to the associated electronic transport properties is the starting point for optimizing the performance of a device and its technological applications. In a hydrogenated ZnCoO (ZnCoO:H) film with an inverted thin-film transistor structure, we found ambipolar behavior, which is shown in many field-effect devices based on graphene, graphene nanoribbons, and organic semiconductors. In this study, to obtain information on the DOS of ZnCoO:H to explain the ambipolar behavior in terms of the carrier density and type, resistivity and magnetoresistance measurements of a ZnCoO:H film were performed at 5 K.

Formation of ferromagnetic Co-H-Co complex and spin-polarized conduction band in Co-doped ZnO.

Magnetic oxide semiconductors with wide band gaps have promising spintronic applications, especially in the case of magneto-optic devices. Co-doped ZnO (ZnCoO) has been considered for these applications, but the origin of its ferromagnetism has been controversial for several decades and no substantial progress for a practical application has been made to date. In this paper, we present direct evidence of hydrogen-mediated ferromagnetism and spin polarization in the conduction band of ZnCoO.

Synergistically Enhanced Electrochemical Performance of Hierarchical MoS/TiNbO Hetero-nanostructures as Anode Materials for Li-Ion Batteries.

As potential high-performance anodes for Li-ion batteries (LIBs), hierarchical heteronanostructures consisting of TiNbO nanofibers and ultrathin MoS2 nanosheets (TNO@MS HRs) were synthesized by simple electrospinning/hydrothermal processes. With their growth mechanism revealed, the TNO@MS HRs exhibited an entangled structure both for their ionic and electronic conducting pathways, which enabled the synergetic combination of one- and two-dimensional structures to be realized. In the potential range of 0.

Efficiencies of Dye-Sensitized Solar Cells with Hollow SnO2 Nanofiber/TiO2 Nanoparticle Composite Photoanodes.

In this study, we present dye-sensitized solar cells (DSSCs) with improved efficiencies by using SnO2/TiO2 composite photoanodes containing SnO2 at various concentrations. The composites consisted of hollow nanofibers (h-NFs) of SnO2 and TiO2 nanoparticles (NPs). The combination of the large surface area of the NPs and the efficient charge transport in the h-NFs make the use of the SnO2/TiO2 composites advantageous.

Template-Directed Directionally Solidified 3D Mesostructured AgCl-KCl Eutectic Photonic Crystals.

3D mesostructured AgCl-KCl photonic crystals emerge from colloidal templating of eutectic solidification. Solvent removal of the KCl phase results in a mesostructured AgCl inverse opal. The 3D-template-induced confinement leads to the emergence of a complex microstructure.

Cu mesh for flexible transparent conductive electrodes.

Copper electrodes with a micromesh/nanomesh structure were fabricated on a polyimide substrate using UV lithography and wet etching to produce flexible transparent conducting electrodes (TCEs). Well-defined mesh electrodes were realized through the use of high-quality Cu thin films. The films were fabricated using radio-frequency (RF) sputtering with a single-crystal Cu target--a simple but innovative approach that overcame the low oxidation resistance of ordinary Cu.

Abnormal drop in electrical resistivity with impurity doping of single-crystal Ag.

Resistivity is an intrinsic feature that specifies the electrical properties of a material and depends on electron-phonon scattering near room temperature. Reducing the resistivity of a metal to its potentially lowest value requires eliminating grain boundaries and impurities, but to date few studies have focused on reducing the intrinsic resistivity of a pure metal itself. We could reduce the intrinsic resistivity of single-crystal Ag, which has an almost perfect structure, by impurity doping it with Cu.

Fabrication of ZnCoO nanowires and characterization of their magnetic properties.

Hydrogen-treated ZnCoO shows magnetic behavior, which is related to the formation of Co-H-Co complexes. However, it is not well known how the complexes are connected to each other and with what directional behavior they are ordered. In this point of view, ZnCoO nanowire is an ideal system for the study of the magnetic anisotropy.

Plasma treatment effect on dye-sensitized solar cell efficiency of hydrothermal-processed TiO2 nanorods.

Atmospheric plasma (AP) treatment was carried out on TiO2 nanorods (NRs) that were hydrothermally grown on F-doped SnO2 (FTO)/glass. The effects of AP treatment on the surface of the TiO2 NRs were investigated, where the treatment involved the use of the reactive gases H2, N2, and O2. The surface energy of AP-treated TiO2 NRs was about 1.

Improving the precision of Hall effect measurements using a single-crystal copper probe.

The circuitry and components of a Hall measurement kit were replaced with single-crystal copper (SCC) wires and parts prepared by a novel wire fabrication process. This process preserved the grain-free structure of SCC grown by the Czochralski method. The new kit was used to determine, with greatly improved precision, the electrical coefficients such as carrier density and mobility, establish the reproducibility of the measured values, and define the semiconductor type.

Effects of TiO2 nanorod length and post-annealing on the electrical properties of TiO2 nanobarbed fiber structures.

TiO2 nanobarbed fiber (NBF) structures consisting of TiO2 nanorods (NRs) on TiO2 nanofibers (NFs) were fabricated. The mean length and diameter of the TiO2 NRs grown for 6 h was 1.38 microm and 71 nm, respectively.

Photocatalytic performance of nanocrystalline Bi5Ti3FeO15 layered perovskite under visible light.

Nanocrystalline Bi5Ti3FeO15 layered perovskite exhibiting Aurivillius phase was synthesized by polymerized complex (PC) method and investigated for its physico-chemical as well as optical properties. The crystallization of Bi5Ti3FeO15 synthesized by PC method was found to occur in the temperature range of 800-1050 degress C, whereas the single crystalline Bi5Ti3FeO15 formed at 1030 degrees C by solid state reaction (SSR) method. The observation of highly pure phase and such lower crystallization temperature in Bi5Ti3FeO15 prepared by PC method, is in total contrast to that observed in Bi5Ti3FeO15 prepared by the conventional solid-state reaction (SSR) method.

Surface plasmon resonance investigation of a copolymer containing spiroxazine.

Spiroxazines are a class of photochromic compounds whose molecular structures are alterable upon exposure to UV/visible light. The typical reaction of spiroxazines is the conversion between the non-polar ring-closure form and polar ring-open form. In this work, copolymer of 1,6-heptadiyne derivatives containing a spiroxazine was used as photochromic material.

Surface modification of and selective protein attachment to a flexible microarray pattern using atmospheric plasma with a reactive gas.

The hydrophobic and hydrophilic properties of the surface of poly-ether sulfone (PES) films were controlled by an atmospheric pressure plasma (AP) treatment using reactive gases (Ar/H(2) and Ar/O(2)). The surface properties of the Ar/H(2) and Ar/O(2) in series AP-treated PES films showed higher surface roughness (approximately 120%), surface energy (approximately 30%) and hydrophilic properties (oxygen content approximately 10%) than the Ar/O(2) AP-treated PES film. The protein staining results confirmed that an activated region on the patterned PES film with high selectivity and sensitivity was well-defined and formed.